Pocket assembly for placing a flat dowel between cast in place concrete slabs

ABSTRACT

An assembly for use in the formation of adjacent concrete slabs to provide a flat rectangular dowel engaged between the slabs. The assembly comprises a pocket which is cast in place in the edge portion of the first slab to be formed, with the dowel fully confined within the pocket. After the formation of the first slab, the dowel is partially withdraw from the pocket and the second slab is formed in place against the first slab, with the dowel in spanning relationship to the respective slabs. In the preferred embodiments, the pocket comprises a monolithic plastic box having complimental generally rigid upper and lower sections movable between a closed condition defining the pocket therebetween and an open condition exposing the pocket interiorly. One edge of the pocket is formed with an opening through which the dowel passes as it moves between the fully confined and the partially withdrawn positions. In certain embodiments, a sealing element or door is provided to close the opening during the formation of the first slab. Seal elements are also provided to seal the pocket against the intrusion of concrete during the formation-of the second slab.

RELATED APPLICATION

This application is based upon and claims the benefit of Provisional Application 60/787,125, filed Mar. 29, 2006.

BACKGROUND OF THE INVENTION

The present invention relates to an assembly for use in the formation of adjacent concrete slabs to provide an embedded flat planar dowel to maintain the slabs in generally horizontal alignment, while permitting limited lateral movement of the slabs relative to one another. In its more specific aspects, the invention is concerned with such an assembly which provides a pocket cast in place within the first slab to be formed and a dowel within the pocket which may be partially withdrawn for embedment within the second slab to be formed.

The provision of dowels to transfer loads between adjacent cast in place concrete slabs is well known. Generally these dowels are a conventional cylindrical configuration. It is also known to provide dowels for this purpose which are of a flat diamond-shape, as may be seen from U.S. Pat. No. 6,354,760. The flat configuration has the advantage that it increases the bearing area of the dowel.

The prior art also teaches the provision of load transferring dowels for adjacent concrete slabs where some type of resilient spacer is provided around part of all of the dowel to accommodate limited movement between the slabs and the dowel. Such arrangements are seen, for example, in U.S. Pat. Nos. 6,354,760; 6,145,262, 5,674,028; 5,040,350; and 4,733,513. In some instances, these spacers comprise a sheath which is cast in place in the edge of a slab, with the dowel in place in the sheath and extending therefrom. The later arrangement may be seen in U.S. Pat. No. 6,354,760.

A disadvantage of the prior art spacers and sheaths is that either the dowel, or some type of a mounting plate is disposed within and extends from the dowel or sheath during its placement within the slab being formed. This requires that the form be configured to accommodate the plate or dowel and also risks that cement may intrude around the dowel and the spacer, during the formation of the concrete slab. Also, in the case where a mounting plate is used, the plate is yet another piece of apparatus which needs to be provided and, ultimately, removed.

SUMMARY OF THE INVENTION

The present invention provides an apparatus and method for positioning a load transferring dowel between adjacent cast in place concrete slabs. The apparatus comprises a pocket forming member having a dowel received therein for movement between a first position fully confined within the pocket of the member and a second position extending partially out of an opening in the pocket. A fastener is provided for securing the member to a form, with the opening in juxtaposition to the form and the dowel fully confined within the pocket. In this basic combination, the form serves to close the opening in the pocket. Additionally, a door or sealing element may be provided to close the pocket, prior to its attachment to the form.

The method comprises first providing a pocket forming member having a pocket therein slidably receiving a dowel for movement between a first position confined within the pocket and a second position extending through an opening formed in one end of the pocket. The remaining method steps comprise:

-   -   1. securing the pocket forming member to an edge forming member         of a form, with the dowel in the first position;     -   2. forming concrete against the forming member to provide a         first concrete slab having the pocket forming member embedded         therein, with the opening disposed at one edge of the slab;     -   3. removing the forming member to expose the opening;     -   4. pulling the dowel partially of the pocket; and     -   5. forming concrete against the edge of the first concrete slab         to provide a second slab having the portion of the dowel         embedded therein.

A principal object of the invention is to provide an assembly which may be used to both form a pocket in the edge of a cast in place concrete slab and provide a dowel which may be partially withdrawn from the pocket and cast in place within an adjacent concrete slab.

Another object of the invention is to provide such an assembly wherein the dowel is of a generally planar configuration, over the length thereof spanning the cast in place slabs.

Still another object of the invention is to provide such an assembly wherein the dowel is laterally confined between resilient members to accommodate relative lateral movement of the slabs.

Still another object of the invention is to provide such an assembly wherein stop or detent elements are provided to enable the dowel to be adjusted to a select position of extension relative to the pocket forming member.

A further object of the invention is to provide such an assembly wherein seals are provided to prevent the intrusion of fluid concrete into the pocket forming member during the formation of a concrete slab.

Yet another object of the invention is to provide such an assembly wherein the pocket in the pocket forming member is fully sealed during the formation of the first to be formed slab.

These and other objects will become more apparent when viewed in light of the accompanying drawings and following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the pocket forming member of a first embodiment of the invention, with the member shown in an open condition exposing the interior thereof;

FIG. 2 is an exploded perspective view of the pocket forming member of FIG. 1, with the member shown in an open condition and a dowel and resilient spacers in the process of being assembled into place;

FIG. 3 is a perspective view of the FIG. 1 pocket forming member, in the closed fully assembled condition;

FIG. 4 is a front elevational view of the fully assembled first embodiment pocket forming member, as it would appear when viewed from the lower left side of FIG. 3;

FIG. 5 is a side elevational view of the fully assembled first embodiment pocket forming member, secured in place to an edge form with a first formed concrete slab poured in place against the form and around the member;

FIG. 6 is a perspective view of the first embodiment pocket forming member, cast in place within a first formed concrete slab, with the dowel received within the member partially extended therefrom;

FIG. 7 is a perspective view similar to FIG. 6, showing a second formed concrete slab poured in place against the first formed slab, with the partially extended portion of the dowel cast in place within the second formed slab;

FIG. 8 is a perspective view of the pocket forming member of a second embodiment of the invention, with the member shown in an open condition exposing the interior thereof;

FIG. 9 is a cross-sectional view taken on the plane designated by line 9-9 of FIG. 8;

FIG. 10 is an exploded perspective view of a metal dowel for use in the second embodiment pocket forming member, with a grip element for the dowel in the process of being placed in a recess therefor formed in the dowel;

FIG. 11 is an exploded perspective view of the second embodiment pocket forming member in the open condition, with the dowel in the process of being placed therein;

FIG. 12 is a cross-sectional view, taken on the plane designated by line 12-12 of FIG. 11;

FIG. 13A is a plan view of the second embodiment pocket assembly, showing the assembly with the top of the pocket forming member open and the dowel fully within the member;

FIG. 13B is a plan view similar to FIG. 13A, but showing the dowel partially extended from the pocket in the pocket forming member;

FIG. 14 is a perspective view of the second embodiment pocket forming member, with the dowel of FIG. 10 shown on place within the member and the door of the member shown in the open condition;

FIG. 15 is a side elevational view of the second embodiment pocket forming member, shown secured to an edge form, with a first formed concrete slab poured in place against the form and around the pocket forming member;

FIG. 16 is a perspective view of the second embodiment pocket forming member cast in place within a first formed concrete slab, with the door of the member removed and the dowel partially withdrawn from the member;

FIG. 17 is a perspective view similar to that of FIG. 16, showing a second formed concrete slab cast in place against the first slab, with the portion of the dowel extending from the pocket forming member embedded within the second formed slab;

FIG. 18 is a perspective view of a composite plastic dowel which may be used in the second embodiment pocket forming member in place of the metallic dowel shown in FIG. 10;

FIG. 19 is a cross-sectional view taken on the plane designated by line 19-19 of FIG. 18;

FIG. 20A a plan view of a third embodiment pocket assembly, showing the assembly with the pocket forming member open and the dowel fully within the member;

FIG. 20B is a plan view similar to FIG. 20A, but showing the dowel partially extended from the pocket in the pocket forming member;

FIG. 21A is an exploded cross-sectional elevational view of the pocket assembly of FIG. 20A, taken on a plane to the interior of the flange of the pocket member;

FIG. 21B is a cross-sectional elevational view taken on the plane designated by line 21B-21B of FIG. 20A;

FIG. 21C is a front elevational view of the fully assembled pocket forming member of the third embodiment, with the door removed and the mounting flange shown;

FIG. 22A is an exploded perspective view of a fourth embodiment pocket assembly, showing the pocket in the open condition and the dowel positioned for insertion into the pocket;

FIG. 22B is a perspective view of the fourth embodiment pocket assembly in the closed condition, with the dowel confined within the pocket and sealing tape in the process of be placed over the opening in the assembly;

FIG. 22C is a perspective view of the fourth embodiment pocket assembly, with the dowel partially withdrawn from the pocket of the assembly;

FIG. 22D is an exploded perspective view, with parts thereof broken away, showing the connection between the upper and lower parts of the mounting flange for the pocket assembly;

FIG. 22E is a side elevational view of the fourth embodiment pocket assembly, with the dowel partially withdrawn from the pocket;

FIG. 22F is a cross-sectional side elevational view of the fourth embodiment pocket assembly, shown secured to a form element with a first concrete slab cast therearound and the dowel confined within the pocket of the assembly; and

FIG. 22G is a cross-sectional side elevational view taken on the plane designated by line 22G-22G of FIG. 22C, showing the fourth embodiment pocket assembly with the dowel partially removed from the pocket and first and second concrete slabs cast in place.

DESCRIPTION OF THE FIRST EMBODIMENT

This embodiment, as seen in FIGS. 1 to 7, comprises as it basic elements a pocket forming member or box P₁ and a dowel D₁. The member P₁ is fabricated of a relatively ridged injection molded polymer, such as low density polyethylene, high density polyethylene, polypropylene, nylon, or propriety polymers known as K-Resin for PRe Tuf. The dowel may be formed of any suitably strong metal, such as steel, or from a suitably strong polymer, such as polyester, polyester with glass or carbon fillers, nylon, or polycarbonate with fillers. The fillers may be a variety of things, such as short or long strand glass, short or long strand glass beads, mineral or talc. The various polymer materials may be either prime, reprocessed, or a combination of prime and reprocessed.

The pocket forming member P₁ is of a monolithic construction and comprises upper and lower sections 10 and 12 with an integral hinge 14 therebetween. The sections 10 and 12 are of a generally trough-shaped cross-section and are formed with inwardly extending protrusions, in the form ribs 16 extending longitudinally thereof. Side walls 18 are formed on the upper section 10 and side walls 20 are formed on the lower section 12. Fastening ears or flanges 22 are formed on and extend outwardly from the sections 10 and 12. Mutually engagable latch elements 24 and 26 are also formed on the upper and lower sections. The latch elements 24 extend outwardly from the walls 18 and are of generally hooked shaped configuration, as may be seen from FIG. 1. The latch elements 26 comprise short extensions extending outwardly from the side walls 20, as may also be seen from FIG. 1.

The dowel D₁ of a rectangular configuration, as viewed in plan, generally complimental to the interior of the pocket forming member. It is movable between a first position fully confined within the pocket forming member (see FIG. 3) and a second position wherein approximately one-half of its length extends out of the open end of the pocket forming member (see FIG. 6). Movement to the second position is limited by resilient stop members 28 received within the pocket forming member P₁ and ears 30 formed on and extending laterally from the rearward edge of dowel D₁. As can be seen from FIG. 2, the width of the dowel D₁ is less than the interior width of the pocket forming member P₁, as measured between the side walls of the pocket forming member. This accommodates limited lateral movement of the dowel relative to the pocket forming member. Typical dimensions for the dowel D₁ are 5 inches deep by 3 inches wide by ⅜ inches thick, with a clearance of ¼ inch between the outside edges of the dowel and the interior of the pocket. The stop members 28 are fabricated of a resilient cushion like material, such as a foam polymer, to accommodate such movement. The stop members are adhered to the interior of the pocket forming member and have a length approximately one-half the length of the pocket forming member. When the dowel is partially withdrawn from the pocket forming member, as seen in FIG. 6, the ears 30 engage with the innermost edges of the members 28 to limit extension of the dowel.

FIG. 2 illustrates how the dowel assembly of the first embodiment is put together. As there seen, the stop members 28 would first be adhered to the interior of the side walls 20 and the dowel D₁ would then be placed between these members in the fully retracted condition. The upper section 10 is then swung to the closed condition so that the latch elements 24, 26 engage to lock the upper and lower sections together in the closed condition, as seen in FIG. 3. In this condition, the dowel is fully confined within the pocket forming member, as seen in FIGS. 3, 4 and 5.

FIG. 5 shows how the dowel assembly of the first embodiment is secured to the edge forming member 32 of a concrete form. As there shown, fastening nails or screws 34 are extended through the ears 22 and into secure engagement with the member 32. This functions to secure the outer surface 36 of the member 32 over the open end of the pocket forming member P₁, thus effectively sealing the pocket against intrusion by the fluid concrete of a first form slab C₁. The step of forming the first formed slab is depicted in FIG. 5. After the slab has sufficiently cured, the next step comprises removing the edge forming member 32 so that the end of the slab, with the pocket opening therethrough, is exposed, as seen in FIG. 6. Then, the dowel D₁ is partially withdrawn through the open end of the pocket, as seen in FIG. 6 and depicted by the arrow lines. Such withdrawal is limited to approximately one-half of the length of the dowel D₁, as seen in FIG. 6, by engagement of the ears 30 with the resilient stop members 28.

The ribs 16 limit contact of the dowel D₁ with the interior of the pocket forming member. This, together with the disposition of the ribs in a direction extending parallel to the direction of movement of the dowel (the arrow lines in FIG. 6) eases and facilitates movement of the dowel to the extended position.

FIG. 7 depicts the placement of the second formed slab C₂ against the first formed slab C₁. As there shown, the slab C₂ is cast directly around the extended end of the dowel D₁ and against the slab C₁. Thus, the dowel has one-half of its length embedded in direct engagement with the slab C₂ and the other half of its length slidably received within the pocket forming member P₁. As so disposed, the upper and lower planar surfaces of the dowel are generally parallel to the upper surfaces of the slab C₁ and C₂ and function to maintain these surfaces in alignment. At the same time, relative expansion and contraction of the slabs towards and away from one another is accommodated by sliding of the dowel within the pocket forming member. The resilient stop members also accommodate limited relative lateral movement of the slabs.

DESCRIPTION OF THE SECOND EMBODIMENT

The pocket forming member of this embodiment is illustrated in FIG. 8 and identified, in its entirety, by the reference letter P₂. The member P₂ is injection molded from the same type of polymer described with reference to the pocket forming member P₁ of the first embodiment. It differs from the first embodiment primarily in that it does not have longitudinally extending ribs within the pocket and in the structure of the stop members and fastening structure. It also differs in that a door 36 is provided to close the opening in the pocket forming member P₂.

The pocket forming member P₂ is similar to the member P₁ in that it comprises upper and lower sections 40 and 42, respectively, hingedly secured together by an integrally formed hinge 44. The upper section is formed with side walls 48 and the lower section is formed with side walls 50. The fastener member of the second embodiment comprises flanges 52 and 54 which provide a collar extending around at the open end of the member P₂. These flanges have open ended slots 56, 58, 60 and 62 extending therethrough for the receipt of nail or screw fasteners used to secure the pocket forming member to the edge forming member of the form. The door 36 is integrally formed with the pocket forming member P₂ and is joined to the flange 54 by an integral hinge 64. Openings 66 extend through the door 36 for alignment with the open ended slots in the flanges 52 and 54 and cutout portions at the lateral edges of the flanges. The cutout portions are seen in FIG. 14 and designated 68.

Latch elements 70, 72, corresponding to the elements 24, 26 of the pocket forming member P₁ are secured to the exterior of the pocket forming member P₂. Interiorally, the pocket forming member P₂ has integrally formed resilient detent members 74, 76. These members are disposed to engage grooves 78, 80 and 82 in the lateral edges of a dowel D₂ received within the pocket forming member P₂ (see FIG. 11). The detents engage the grooves 78, 80 to hold the dowel D₂ in a position fully confined within the pocket forming member P₂, as seen in FIG. 13A, and are inwardly deflectable responsive to pulling of the dowel to enable the dowel to be partially withdrawn from the pocket forming member, as seen in FIG. 13B. In the later condition, the detent members 76 are held in a compressed condition against the sides of the dowel to form a seal against the intrusion of fluid concrete into the pocket forming member and the detent members 74 are engaged with a flange 84 on the inner end of the dowel D₂ to limit extension of the dowel from the pocket forming member.

FIG. 9 shows a thin wiper edge 86 which extends around the opening in the pocket forming member P₂. This edge is disposed to engage the side surfaces of the dowel D₂ to seal the pocket within the member P₂ against the intrusion of fluid concrete.

FIG. 14 shows the pocket forming member P₂ in the closed condition with the dowel D₂ fully received within the pocket. As there shown, the latch elements 70, 72 are engaged to hold the upper and lower sections of the pocket forming member together and the door 36 is in the open condition. The curved line depicts how the door 36 hingedly moves to a closed condition disposed over the open end of the pocket forming member.

FIG. 15 shows the pocket forming member P₂ secured to an edge forming member 32, with the door 36 closed so as to be interposed between the member 32 and flanges 52 and 54. Nails or screws 34 extend through the openings therefore in the flanges and into secure engagement with the member 32.

As shown in FIG. 15, a first formed slab C₁ is formed in place around the pocket forming member P₂ and against the edge forming member 32. FIG. 16 depicts the next step wherein the edge forming member 32 has been removed, the door 36 has been torn away, and the dowel D₂ has been partially withdrawn from the pocket forming member, as depicted by the arrow line. As shown, the partially withdrawn position is that of FIG. 13B wherein the flange 84 is engaged with the detent member 74 and the detent members 76 are compressed into sealing engagement with the side surfaces of the dowel. FIG. 17 shows the next step wherein a second formed slab C₂ is formed in place against the edge surface of the slab C₁. As there shown, the dowel D₂, has its distal half directly embedded in the slab C₂ and its proximal end received in the pocket forming member P₂. As thus positioned, the dowel functions to maintain the slabs C₁, and C₂ in horizontal alignment, while permitting their expansion and contraction relative to one another and also permitting limited lateral movement therebetween. Such limited lateral movement is accommodated by compression of the detent members 74, 76.

The dowel D₂ is manufactured of a metallic material, such as steel. In plan view, it is of a rectangular configuration generally complimental to that of the pocket formed within the pocket forming member P₂. Typical dimensions for the dowel D₂ are 3 inches deep, by 5 inches wide, by ⅜ inch thick, with a clearance of ¼ inch between the side edges of the dowel and the interior of the pocket. The forward edge of the dowel is formed with a trapezoidal cutout 88 for receipt of a complimental finger grip insert 90. The insert may be formed of any suitable material, such as injected molded polymer. Its cross-section is shown in FIG. 12, wherein recesses 92 are formed to either side of a flared web 94.

FIGS. 18 and 19 show a dowel D₃ formed in its entirety of a polymer and designed for use as a substitute for the dowel D₂. Dowel D₃ may be formed of any of the high strength polyesters heretofore described for use in making such a dowel. It has a configuration essentially identical to that of the dowel D₂, except that the grip portion thereof is integrally formed with the dowel and the recess for the grip is flared outwardly, rather than inwardly. Elements of the dowel D₃ corresponding to those of the dowel D₂ are designated by like reference characters. In the cross-section of FIG. 19, the flared web is designated 96 and the recesses to either side thereof are designated 98.

DESCRIPTION OF THE THIRD EMBODIMENT

The pocket forming member of this embodiment is identified, in its entirety, by the reference letter P₃. The member P₃ is injected molded from the same type of polymer described with reference to the pocket forming members P₁ and P₂ of the first and second embodiments. It comprises an upper section 100 and a lower section 102 disposed for movement toward one another, as depicted in FIG. 21A, and is similar to the second embodiment in that it has a flanged open end (see FIG. 21C). The flanged open end is provided by a first flange 104 on the upper section 100 and a second flange 106 on the lower section 102, These flanges are similar to the flanges 52, 54 and are formed with open ended slots 105, 107.

The sections 100 and 102 differ from the sections 40 and 42 of the second embodiment in that the upper section 100 is of a shallower depth than the upper section 40 and in that the sections are not hingedly joined. Rather, they are provided with four sets of paired latch elements 70, 72. These elements snap into engagement, to secure the sections 100 and 102 together, as seen in FIG. 21B. Dowel D₄ is positioned so as to be fully within the lower section 102, before the sections 100, 102 are snapped together.

The dowel D₄ is of a thinner construction then the dowels D₁, D₂ and D₃ and also differs in construction from these dowels in that it is so proportioned that spaces 108 and 110 are provided to the sides and rear of the dowel, when it is received within the pocket member P₃ (see FIG. 20A). Typical dimensions for the dowel D₄ are 3 inches deep, by 5 inches wide, by ¼ inch thick, with the spaces 108 and 110 measuring approximately ¼ inch. Another difference is that the left hand side of the dowel D₄, as viewed in FIG. 20A, is smooth. This side is designated by the numeral 112. The right side of the dowel D₄ is formed with paired notches, designated 114, 116, 118 and 120. These notches cooperate with a bifurcated detent spring having legs 122 and 124 for engagement with the paired notches to secure the dowel in either the extended or retracted position. When in the extended position, the legs 122, 124 engage sharp edges 126, 128 on the recesses 118, 120 to lock the dowel D₄ in the condition shown in FIG. 20B and against both inward and outward movement relative to the pocket member P₃.

The lower section 102 of is formed with spring leaves 130 and 132 (see FIG. 20A). The leaves 130 permit some compression of the dowel D₄ into the pocket forming member P₃. The leaves 132 engage the side 112 and force the dowel into engagement with the legs 122 and 124 (see FIGS. 20A and 20B). Leaves 132 also permit lateral movement of the dowel D₄ relative to the pocket forming member P₃, when the assembly is cast and placed between adjacent concrete slabs.

In use, the third embodiment pocket assembly and dowel is placed in first and second formed concrete slabs in a manner identical to that of the pocket forming member P₂ and dowel D₂ of the second embodiment. In the resulting concrete structure, the only difference being that the dowel is of a thinner configuration and that the leaves and detent members operate somewhat differently, as described above.

The different depths of the upper and lower sections 100 and 102, and the absence of a hinged connection therebetween, enable two sections corresponding generally to the section 100 to be mated together to accommodate a thinner dowel, or that two thick sections, such as the section 106, to be mated together to accommodate an thicker dowel. This adds to the versatility of the third embodiment, without the necessity of providing special molds for the manufacture of different upper and lower sections. To accommodate such a combination of two thin or two thick sections, the latch elements 70, 72 would be constructed so that they could snap together, irrespectively of the combination in which the sections were assembled.

DESCRIPTION OF THE THIRD EMBODIMENT

The pocket forming member of this embodiment is identified by the reference letter P₄. The member P₄ is injection molded from the same type of polymer described with reference to the pocket forming members P₁, P₂ and P₃. It is similar to the pocket member P₁ in that it comprises upper and lower sections 132 and 134, respectively, hingedly secured together by an integrally formed hinge 136. The upper section is formed with sidewalls 138 and the lower section is formed with sidewalls 140. An end wall 142 extends between the sidewalls 138 and an end wall 144 extends between the sidewalls 140.

The fastener member of the fourth embodiment comprises flanges 146 and 148 which provide a collar extending around the open end of the member P₄. These flanges have integrally formed complimental U-shaped fasteners 150, 152 formed on the interior surfaces thereof (see FIG. 22D). When the fasteners are complementally engaged, as seen in FIG. 22C, a nail 154 is extended through the fasteners and two-part aperture 156 aligned therewith. The nail serves to lock the fasteners 150, 152 together and hold the upper and lower sections of the member P₄ in the closed condition. In use, the nail 154 extends fully through the flanges 146, 148 and into engagement with the edge forming member 32 of a concrete form. Nails or screws may also be extended through a centrally disposed support 158 on the upper section 132 (see FIG. 22C) to centrally fasten the flange 148 to the edge forming member 32. The support 158 is integrally formed with the upper section 132 and functions to reinforce the flange 148. Similar reinforcements are provided by triangular elements 160, integrally formed with the respective upper and lower sections 132 and 134 (see FIG. 22E).

The dowel of the fourth embodiment, designated D₅, may be fabricated of metal or a polymer material similar to that described with reference to the dowel D₁. It also has similar dimensions to the dowel D₁ and is of a plan configuration complimental to that of the pocket in the pocket forming member P₄, with space provided for between the dowel and the interior sidewalls of the pocket to accommodate limited lateral movement of the dowel relative to the pocket. Resilient spacers 161 are formed integrally with the section 134 to, at least initially, maintain the dowel D₅ in alignment with the member P₄. A tongue 162 is integrally formed with the dowel D₅. When the dowel is retracted into the pocket member P₄, the tongue 162 is fully confined within the member (see FIG. 22B). The tongue serves as means to pull the dowel to the extended position, as seen in FIG. 22G. Pulling may be achieved through means of a plier-like tool.

The dowel D₅ has an aperture 164 extending therethrough for receipt of an expansible spring pin 166. Grooves 170, 172 are formed in the upper and lower sections 132, 134, respectively, in alignment with the aperture 164 for slidable receipt with the ends of the pin 166. The grooves have integrally formed detent ramps 174, 176 for engagement by the ends of the spring pin 166. Ramps 176 are tapered on their forward and trailing edges to enable the pin to slide thereover in either direction. The ramps 174 are tapered on the side thereof facing to the interior of the pocket and are formed with abrupt edges 178 on the sides thereof facing the open end of the pocket member P₄. As a result of this construction, the pin 166 may ride over the ramps as the dowel D₅ is pulled out of the pocket forming member P₄ from the retracted (first) position. When the pin reaches a position to the outside of the ramp 174, it snaps into place in the recess between the edges 178 and an end wall 179, as seen in FIG. 22G, to latch the dowel in the extended (second) position and hold the dowel against further withdrawal or retraction relative to the member P₄.

The manner of assembling the fourth embodiment may be seen from FIG. 22A. As there seen, the dowel D₅ would be lowered into the lower section 134, with the pin 166 in place within the aperture 164. The upper section would then be swung to the closed condition, as depicted by the arcuate arrow line. As the upper section swings into the closed condition, latch elements 180 thereon engage over the edges of the lower section 134 to lock the upper and lower sections together.

The final step of conditioning the fourth embodiment for use is shown in FIG. 22B, wherein adhesive tape is being placed over the open end of the pocket to close the end against fluid intrusion by concrete. The tape has a tear line 182 extending longitudinally thereof to facilitate its tearing when access to the dowel is desired.

Tapered edges 183 on the flanges 146, 148 engage the sides of the dowel D₅ (see FIG. 22A). These edges provide wipers which engage the dowel D₅ as it is drawn out of the pocket forming member. They serve to seal the interior of the pocket against intrusion by fluid concrete, when a second slab C₂ is formed.

In use, the member P₄ is fastened to an edge forming member 32, as seen in FIG. 32. A first concrete slab C₁, is then formed therearound, with the result that the pocket forming member P₄ is cast within the slab, with the mounting flange thereof juxtaposed to the edge forming member 32. Once the concrete of the slab C₁ has sufficiently cured, the edge forming member 32 is removed, the tape T is torn away, and the dowel D₅ is moved to the extended position, as shown in FIG. 22G. A slab C₂ is then formed in place, resulting in approximately one-half of the length of the dowel D₅, being embedded within the slab C₂ and the other half being disposed in the pocket member P₄, within the slab C₁.

As shown the rearward end dowel D₅ is shown formed with a cutout of the same shape as tongue 162. This cutout performs no function. It is the result of a stamping process wherein successive dowels D₅ are stamped from a common sheet of metal.

CONCLUSION

While preferred embodiments have been illustrated and described, it should be understood that the invention is not limited to these embodiments, but rather is defined by the accompanying claims. 

1. A dowel assembly for use in for use in the formation of adjacent concrete slabs to maintain the slabs in alignment, comprising: a. a pocket forming member having a pocket therein, said member having an opening in one end communicating with the pocket; b. a dowel received within the pocket for movement between a first position fully confined within the pocket and a second position extending through the opening and partially out of the pocket; and, c. a fastener for securing the member to a form with the opening in apposition to the form and the dowel fully confined within the pocket.
 2. A dowel assembly according to claim 1, further comprising a first stop on the pocket forming member for engagement with the dowel to limit the degree to which the dowel can be withdrawn from the pocket for movement to the second position.
 3. A dowel assembly according to claim 2, further comprising a second stop on the pocket forming member for engagement with the dowel to prevent the dowel from moving from the second to the first position.
 4. A dowel assembly according to claim 1, further comprising a latch interposed between the pocket member and dowel to lock the dowel in the second position upon movement of the dowel from the first position to the second position.
 5. A dowel assembly according to claim 4, wherein the latch comprises: a. a spring biased pin carried by the dowel; and, b. a first pin receiving recess in the pocket member disposed for engagement by the pin upon movement of the dowel to the second position.
 6. A dowel assembly according to claim 5, further comprising a second pin receiving recess in the pocket forming member for engagement with the pin to releasably secure the dowel in the first position, said second recess having a ramped surface to release the pin in response to force moving the dowel from the first position to the second position.
 7. A dowel assembly according to claim 2, wherein: a. the pocket is of a generally rectangular configuration, as viewed in plan; and, b. the dowel is of a rectangular planar configuration generally complimental to that of the pocket.
 8. A dowel assembly according to claim 7, wherein the dowel is width less than that of the pocket to allow limited lateral movement of the dowel relative to the pocket.
 9. A dowel assembly according to claim 8, further comprising a resilient element engaged between the pocket and dowel to urge the dowel into alignment with the pocket while permitting limited lateral movement of the dowel relative to the pocket.
 10. A dowel assembly according to claim 9, wherein: a. the resilient element comprises at least one detent engageable with a lateral edge of the dowel; and, b. the lateral edge of the dowel is formed with notches disposed for engagement with the detent to selectively secure the dowel in either the first or second position.
 11. A dowel assembly according to claim 9, wherein the first stop comprises interengageable surface on the dowel and resilient element, disposed to engage one another when the dowel is moved to the second position.
 12. A dowel assembly according to claim 1 wherein the opening is so disposed relative to the fastener that a form to which the fastener is secured covers the opening.
 13. A dowel assembly according to claim 1, wherein the member comprises complimental upper and lower sections disposed for movement between an open condition exposing the pocket interiorly and a closed condition defining the pocket therebetween.
 14. A dowel assembly according to claim 13, further comprising a hinge connection securing the upper and lower sections together for movement between the open and closed conditions.
 15. A dowel assembly according to claim 13, wherein the upper and lower sections are of different depths and may be assembled in different combinations to alter the depth of the pocket formed therebetween.
 16. A dowel assembly according to claim 13, further comprising a latch to secure the upper and lower sections in the closed condition.
 17. A dowel assembly according to claim 13, wherein the fastener comprises flanges formed on the upper and lower sections for alignment to form a collar around the pocket forming member when the upper and lower sections are in closed condition.
 18. A dowel assembly according to claim 17, further comprising apertures formed in elements carried by the respective flanges for alignment when the upper and lower sections are in closed condition, said elements being adapted to have a nail extended through the aligned apertures thereof to lock the sections in the closed condition and secure the collar formed by the flanges to a form element.
 19. A dowel assembly according to claim 1, further comprising protrusions formed on the member interiorly of the pocket for engagement with the dowel to ease movement of the dowel between the first and second positions.
 20. A dowel assembly according to claim 19, wherein: a. the dowel is disposed to move between the first and second positions in a generally rectilinear path; and b. the protrusions comprise ribs extending in a direction parallel to the path.
 21. A dowel assembly according to claim 1, further comprising a closure element on the member to close the opening.
 22. A dowel assembly according to claim 21, wherein the closure element comprises a door hingedly secured to the member to one side of the opening for movement between open and closed conditions relative to the opening.
 23. A dowel assembly according to claim 22, wherein the door is hingedly secured to the member by a friable connection and the connection may be broken to completely remove the door from the member.
 24. A dowel assembly according to claim 21, wherein the closure element comprises tape adhesively secured to the member.
 25. A dowel assembly according to claim 1, wherein the fastener comprises a flange on the housing extending laterally of the opening.
 26. A dowel assembly according to claim 25, wherein the flange comprises tabs disposed around the opening at spaced intervals.
 27. A dowel assembly according to claim 25, wherein the flange comprises a collar extending around the opening.
 28. A dowel assembly according to claim 1, further comprising a seal element mutually engaged between the pocket forming member and the dowel to seal the pocket against fluid intrusion when the dowel is in the second position.
 29. A dowel assembly for use in for use in the formation of adjacent concrete slabs to maintain the slabs in alignment, comprising: a. a pocket forming member having a pocket therein of a generally rectangular configuration, as viewed in plan, said member having an opening in one end communicating with the pocket; b. a dowel received within the pocket for movement between a first position fully confined within the pocket and a second condition extending through the opening and partially out of the pocket, said dowel being of a rectangular configuration generally complimental to that of the pocket; c. a grip element on the dowel accessible through the opening to enable to dowel to be accessed for select manual movement between the first and second positions; and, d. a fastener for securing the member to a form with the opening in apposition to the form and the dowel fully confined within the pocket.
 30. A dowel assembly according to claim 29, wherein the dowel is width less than that of the pocket to allow limited lateral movement of the dowel relative to the pocket.
 31. A dowel assembly according to claim 30, further comprising a resilient element engaged between the pocket and dowel to urge the dowel into alignment with the pocket while permitting limited lateral movement of the dowel relative to the pocket.
 32. A dowel assembly according to claim 31, wherein: a. the resilient element comprises a detent engageable with a lateral edge of the dowel; and, b. the lateral edge of the dowel is formed with notches disposed for engagement with the detent to selectively secure the dowel in either the first or second position.
 33. A dowel assembly according to claim 31, further comprising interengageable surfaces on the dowel and resilient element disposed to stop the dowel when it moves from the first to the second position.
 34. A dowel assembly according to claim 33, further comprising second interengageable surfaces on the dowel and resilient element to prevent the dowel from moving from the second to the first position.
 35. A dowel assembly according to claim 29, wherein the opening is so disposed relative to the fastener that a form to which the fastener is secured covers the opening.
 36. A dowel assembly according to claim 29, wherein the member comprises complimental upper and lower sections disposed for movement between a closed condition defining the pocket therebetween and an open condition exposing the pocket interiorly.
 37. A dowel assembly according to claim 36, further comprising a hinge connection securing the upper and lower sections together for movement between the open and closed conditions.
 38. A dowel assembly according to claim 36, further comprising a latch to secure the upper and lower sections in the closed condition.
 39. A dowel assembly according to claim 29, further comprising protrusions formed on the member interiorly of the pocket for slidable engagement with the dowel to ease movement of the dowel between the first and second positions.
 40. A dowel assembly according to claim 39, wherein: a. the dowel is disposed to move between the first and second positions in a generally rectilinear path; and b. the protrusions comprise ribs extending in a direction parallel to the path.
 41. A dowel assembly according to claim 29, further comprising a closure element on the member to close the opening.
 42. A dowel assembly according to claim 41, wherein the closure element comprises a door hingedly secured to the member to one side of the opening for movement between open and closed conditions relative to the opening.
 43. A dowel assembly according to claim 42, wherein the door is hingedly secured to the member by a friable connection and the connection may be broken to completely remove the door from the member.
 44. A dowel assembly according to claim 41, wherein the closure element comprises tape adhesively secured to the member.
 45. A dowel assembly according to claim 29, wherein the fastener comprises a flange on the housing extending laterally of the opening.
 46. A dowel assembly according to claim 45, wherein the flange comprises tabs disposed around the opening at spaced intervals.
 47. A dowel assembly according to claim 45, wherein the flange comprises a collar extending around the opening.
 48. A dowel assembly according to claim 29, further comprising a seal element engaged between the pocket forming member and the dowel to seal the pocket against fluid intrusion when the dowel is in the second position.
 49. A method of forming adjacent concrete slabs with an dowel engaged therebetween to maintain the slabs in alignment, said method comprising: a. providing a pocket forming member having a pocket therein slidably receiving a dowel for movement between a first position fully confined within the pocket and a second position extending partially out of the pocket and through an opening formed in one end of the pocket; b. securing the pocket forming member to an edge forming member of a form, with the dowel fully confined within the pocket and the opening covered by the form; c. forming concrete against the forming member to provide a first concrete slab having the pocket forming member embedded therein with the opening disposed at one edge of the slab; d. removing the forming member to expose the opening; e. pulling a portion of the dowel partially out of the pocket; and, f. forming concrete against the one edge of the first concrete slab to provide a second slab having the portion of the dowel embedded therein.
 50. A method according to claim 49, wherein a closure element is provided on the pocket forming member to cover the opening when the dowel is fully confined within the pocket and further characterized in that: a. when the pocket forming member is secured to the edge forming member of a form, the closure element is in place over the opening; and, b. when the forming member is removed, the closure element is also removed.
 51. A method according to claim 49, wherein: a. the pocket forming member is secured to the edge forming member in a horizontal disposition and is of an expansive generally rectangular configuration, as viewed in plan; and, b. the dowel is of an rectangular configuration generally complimental to that of the pocket.
 52. A method according to claim 49, further comprising providing a seal between the pocket forming member and dowel to seal the pocket against concrete intrusion during formation of the second slab.
 53. A dowel for embedment in adjacent concrete slabs to maintain the slabs in alignment, said dowel comprising: a. a rigid body of a generally rectangular configuration, as viewed in plan, said body having side and end edges, b. a recess formed in the body and opening though an end edge thereof, said recess having a finger grip disposed therein.
 54. A dowel according to claim 53, wherein: a. the recess comprises a notch formed in the end edge of the body through which the recess opens; and, b. the grip comprises a rib extending across the notch.
 55. A dowel according to claim 54, wherein: a. the notch extends through the body and is of a trapezoidal configuration, as viewed in plan, with a narrow portion thereof at the edge of the body through which the recess opens and a wider portion thereof disposed internally of the body; and, b. the grip is formed on a member received within and complimental to the notch.
 56. A dowel according to claim 54, wherein a detent notch is formed in a side edge of the body. 